1. Field of the Invention
The present invention relates to a method of assigning a service and an information processing apparatus for implementing the method. For example, the present invention relates to a method of assigning a service with which services distributed on a network are combined and provided as a service framework while taking power consumption into consideration, and an information processing apparatus for implementing the method. More specifically, the present invention relates to a method of assigning a service that efficiently consumes the power of devices that provide the service, and an information processing apparatus for implementing the method.
2. Description of the Related Art
Along with the advancement of network technologies in recent years, the number of server devices, as information processing apparatuses, that provide such a service framework is increasing. In such a service framework, services that are distributively provided over a network are combined and provided as a new service, or a plurality of services are provided as a workflow of tasks.
As a supply source of such services, not only servers and computers, but also image forming apparatuses increasingly provide a variety of services along with the trend toward image forming apparatuses with more functionality and higher performance. Examples of services provided by image forming apparatuses include, in addition to conventional services such as a print service and a fax service, an OCR (optical character recognition) service, a document format conversion service, and so on.
In terms of energy conservation, techniques for reducing power consumption are applied to image forming apparatuses, such as, for example, enabling the printer engine itself to operate at low power levels, or incorporating a mechanism that causes the apparatus to go into a sleep mode when not in use so as to achieve power conservation.
Sleep mode refers to a mode in which the image forming apparatus automatically reduces the power supplied to each component apparatus thereof when, for example, the image forming apparatus is not used for a prescribed period of time. The component apparatuses that are operated at reduced power are, for example, a display panel, a printer engine, and so on. When used during a sleep mode, the image forming apparatus restarts power supply to each component apparatus that was operating at reduced power and starts processing.
Moreover, the sleep mode may be a set of a plurality of modes according to the sleep status, rather than a single mode. For example, the image forming apparatus goes into a first sleep state when not in use for a prescribed period of time, and switches to a second sleep state when not in use for another prescribed period of time after the first sleep state. Here, the first sleep state is a mode that reduces power supply to the component apparatuses that can soon return from the sleep state when power supply is restarted. The second sleep state is a mode that reduces power supply to the component apparatuses that require a warm-up time or the like, or in other words, that require some time to return from the sleep state, such as a printer engine. Generally, power consumption of the second sleep state is reduced below that of the first sleep state, and the second sleep state requires more time from which to return.
A method for reducing the power consumption of a plurality of image forming apparatuses connected to a network is disclosed in, for example, Japanese Patent Laid-Open No. 2000-322161. According to this method, the load of an entire network to which a plurality of image forming apparatuses are connected is measured. The load is the amount of processing requested per unit time, and can be, for example, the number of printed pages per minute. Then, the image forming apparatuses connected to the network are controlled so as to go into a sleep state such that the load value does not fall below a value provided by the entire network while minimizing the power consumption.
The above conventional technique, however, controls the image forming apparatuses so as to go into a sleep state according to a load value that varies from time to time, and does not give consideration to the image forming apparatuses automatically going into a sleep mode. Accordingly, it is not possible to control power consumption so as to reduce it to a minimum according to the services provided by individual image forming apparatuses.
The above problem is not limited to image forming apparatuses, and such a problem occurs similarly in many apparatuses that have a sleep mode.